Global Patent Index - EP 0337708 A3

EP 0337708 A3 19900516 - IMPROVEMENTS IN OR RELATING TO INTEGRAL FINNED TUBES AND A METHOD OF MANUFACTURING SAME

Title (en)

IMPROVEMENTS IN OR RELATING TO INTEGRAL FINNED TUBES AND A METHOD OF MANUFACTURING SAME

Publication

EP 0337708 A3 19900516 (EN)

Application

EP 89303526 A 19890411

Priority

GB 8808919 A 19880415

Abstract (en)

[origin: EP0337708A2] Manufacture of integral finned tube utilising a succession of plugged convergent, cold draw die stages. To produce a tube 70 (Fig. 6) with diametrically opposed integral fins 72 an initial stage die has an exit with an approximately elliptical outer periphery to form a tube with diametrically opposed thicker, or bulged walls. An intermediate stage has an exit of generally circular periphery with a pair of part circular, diametrically opposed, recesses to form a tube 44 (Fig. 4) with more pronounced bulges 45. A final stage die has an exit of generally circular periphery with a pair of diametrically opposed, straight sided recesses to form a tube 70 with bulges constituting planar faced fins 72. Between each successive stage the circumferential extent of each bulge is reduced whilst the maximum thickness is increased.

IPC 1-7

B21C 37/20

IPC 8 full level

B21C 37/20 (2006.01); F28F 1/16 (2006.01)

CPC (source: EP US)

B21C 37/202 (2013.01 - EP US); F28F 1/16 (2013.01 - EP US); Y10T 29/49385 (2015.01 - EP US)

Citation (search report)

Designated contracting state (EPC)

BE DE ES FR GB IT NL

DOCDB simple family (publication)

EP 0337708 A2 19891018; EP 0337708 A3 19900516; GB 8808919 D0 19880518; US 5036693 A 19910806

DOCDB simple family (application)

EP 89303526 A 19890411; GB 8808919 A 19880415; US 33785489 A 19890414